Taxon Report

Malacothamnus marrubioides (Durand & Hilg.) Greene

Santa Clarita bushmallow

Print Report


© 2016 Keir Morse

Taxon Summary

Malacothamnus marrubioides, commonly known as Santa Clarita bushmallow, is a perennial deciduous shrub in the Malvaceae that is found only in California. It occurs within Chaparral, Cismontane woodland, and Riparian woodland, growing at elevations from 55 to 1170 meters. Malacothamnus marrubioides is ranked 4.2, Plants of Limited Distribution, A Watch List; Moderately threatened in California.

  Classification
Scientific Name:
 Malacothamnus marrubioides (Durand & Hilg.) Greene
Common Name:
 Santa Clarita bushmallow
Family: Malvaceae
Element Code: PDMAL0Q0A0
USDA Plants Symbol: MAMA3
Synonyms/Other Names:

Ecology and Life History
Lifeform: perennial deciduous shrub
Blooming Period: (Jan-Mar)Apr-Jul(Aug-Dec) (Jan-Mar)Apr-Jul(Aug-Dec)
Elevation: 55-1170 (180-3840)
General Habitats: Chaparral, Cismontane woodland, Riparian woodland
Microhabitat:
Microhabitat Details: Fire-adapted; populations usually peak after burning occurs.

Conservation Status
CA Rare Plant Rank: 4.2
Global Rank: G3?
State Rank:
 S3
State List: None
Fed List: None
Other Status:
CRPR Changes:
  • added to 4.2 on 2025-09-03

Occurrence Data from the CNDDB
Total Occurrences: 0
Element Occurrence Ranks:
   Excellent (A) 0
   Good (B) 0
   Fair (C) 0
   Poor (D) 0
   None (X) 0
   Unknown (U) 0

Location
California Endemic:  True
California Counties and Islands: Name (Code)
Ventura (VEN)
Quads: Name (Quad Code)
Acton (3411842), Agua Dulce (3411843), Black Mtn. (3411867), Cobblestone Mtn. (3411857), Green Valley (3411854), Liebre Mtn. (3411866), Mint Canyon (3411844), Moorpark (3411838), Newhall (3411845), Pacifico Mountain (3411841), San Fernando (3411834), Santa Paula (3411931), Val Verde (3411846), Warm Springs Mountain (3411855), Whitaker Peak (3411856)

Threat List Data from the CNDDB

Threat List Total: 0
EOs with Threat Listed: Total EOs % of EOs
0 0 %

Notes
Most similar to the inland form of M. foliosus, which is allopatric. Intermediates with M. fasciculatus var. laxiflorus and M. orbiculatus are common where their ranges meet M. marrubioides.
Threats:
Threatened by development and hybridization. Potentially threatened by altered fire regimes and competition from non-native plants.
Taxonomy:
See Leaflets of Botanical Observation and Criticism 1(15): 208 (1906) for original description.

Selected References

CNPS Status Review: Proposed addition to CRPR 4.2, G3 / S3 (2025)
Malacothamnus 3 (2023)
Malacothamnus 3 (2023)
Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 15 November 2025].